<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
<style>
div {
  width: 100px;
  height: 100px;
  background-color: brown;
}

div:nth-child(2) {
  background-color: orange;
}

span {
  width: 200px;
  height: 200px;
  background-color: brown;
}

span:nth-child(4) {
  background-color: orange;
}

img:nth-child(9) {
  width: 100px;
  height: 100px;
}

</style>


<div>div 标签</div>
<div>div 标签</div>
<br>
<span>span 标签</span>
<span>span 标签</span>
<br><br>

<img src="./images/1.png" alt="">
<img src="./images/1.png" alt="">
</body>
</html>